I would bet money this happened. No way that shaft bent from torque. It got hung up on something. As someone else said, if you did hit something and locked up so hard that the shaft had to give, it would have twisted it. Not bent it like that. The only way that can happen is from sideways force on the middle of the driveshaft. The first thing I thought when I saw it is that there isn't enough clearance on the mower deck, and lifting it caused the deck to run in to the shaft and bend it. Hitting the trailer hitch or drawbar makes a lot of sense.